Force multipliers or pressure transmitters that produce an electrical output are commercially available. However, they are not without their drawbacks or shortcomings. First, they are typically relatively expensive and are not usually capable of responding with great sensitivity and accuracy, especially with respect to low pressures. Put simply, there are not many force multipliers or pressure transmitters commercially available today that are relatively inexpensive and which have the capacity to measure full scale on the order of 0.010 inch of water column. To even approach this range of sensitivity with any reasonable degree of accuracy results in the instrument being both relatively large and expensive. This is because force multipliers and pressure transmitters of the past that are capable of producing an electrical output have been designed around diaphragms, fulcrums, and levers. Besides the obvious disadvantages associated with size, this design approach gives rise to other problems as well.
With a conventional fulcrum and lever design, one has moving points, friction, and slop in the connecting linkage. All of this gives rise to hysteresis problems which contribute greatly to inaccuracies of the force multiplier.
Added to this is the basic problem that comes about due to the diaphragm itself being the measuring element. For very small movements of the diaphragm, there is obviously an output. Yet, the very small movements of the diaphragm may be design related or internally generated, and not in any way be a result of a force or pressure change acting on the diaphragm of the instrument. The obvious result of this is a most inaccurate instrument that cannot be relied upon and which has very poor repeatability.